Electric self-playing grand piano.



C. W. DORRICOTT. ELECTRIC SELF PLAYING GRAND PIANO. APPLICATION men JULY 3, I912.

1,213,166. Patented $11.23, 1917.

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C. W. DORRICOTT, ELECTRIC SELF PLAYING GRAND PIANO,

APPLICATiON FILED JULY 3, 1912.

1.213.166. Patented Jan.23,19 17.

3 SHEETS-SHEET 2.

C. W. DORRICOTT. ELECTRIC SELF PLAYING GRAND PIANO.

3 SHEETS-SHEET 3.

Patented Jan. 23, 191?.

APPLICATION FILED JULY 3, I912.

UNITED TATES PA ENT orr on.

CHARLES w. 1303mm, or PHILADELPHIA, PENNSYLVANIA, AssmNon :uo ELEU TBELLE COMPANY, or PHILADELPHIA, PENNSYLVANIA, A CORIORATION 0F PENN- SYLVANIA. f

0 all'whom it may concern:

Beit known that I, CHARLES \V.,Do1inico'r'r, a citizen of the United States, residing 1 My invention further comprehends vari,

ous devices for adjusting the movable arm'a-, tures, and also for regulating at willthe length of the tapes employed to connect the actuating shoes, controllable by the armatures, with the levermechanism for actuating the hammer action of the piano.

My invention also relates to the manner,

in which the various parts are mounted within and upon the magnet bar in order to facilitate the accessibil ty of such parts and to promote the ease with which they may be adjusted, removed or replaced.

My lnvention further relates tothe various improvements for increasing the efliciency of mechanisms of this kind.

Reference is made'to theaccompanying drawings forming-a part of this specification, and in which like letters indicate like parts. 7 o j Fi 'ure l is a side view Jartl 1 1n eleva- 'tion and partly-in sc'ctiomshowing myimtical longitudinal section tlllOllfLll a grand 'piano provided with mylnventlon.

Fig. is a detail showing in section the magnet bar and various parts carried thereby or adjacentthereto. Fig. l isa fragmentary inverted plan, or bottom \'iew.. of the magnet bar and parts connected therewith.

Fig.

is a fragmentary section-through another form of my device, showing the armature mechanism as diiferinggylightly from that shown in Fig. 3. Fig. :6 is a detail showing, in cross section one of the actuating shoes, and a clip carried by it for controlling' the length of one of the actuating tapes. Fig.

'- ELECTRIC SELF-PLAYING GRAND PIANO.

Specification of Letters Patent.

Application filed July 3, 1912. V Serial No. 707,523.

,which is shown at 12.

motor Patented Jan. 23, 1917.

T is a perspective showing one of the actuating shoes. I f

. The casing of a' grand piano is shownuat S, andisprovided with a horizontally d1sposed board 9 serving as a key bed. A-bove this board are the key levers, one of which is shown at 10. Ahammer action appears at 11, and isprovided with hammers, one of Above, the hammers are strings, one appearing at 13, {and in being shown at' l l. I

Each damper. lei is connected with a connection with the strings arev dampers, one

damper lever 1.5'by aid of a rod 16,- Each damper lever 15 is provided with a projecting portion 17wh'ich carries a stop pin 18,

the lower part of this pin being provided with felt.

.carries an enlarged portion 24 at its upper end, the said reduced portion or stem extending through an opening m a plate 25,

as more clearly shown in Fig. 2, the said plate serv ng as a guide for the striker bar during the movements thereof and also as a limiting stop for the striker bar, since the enlarged portion 24, thereofnormally rests upon the 'plate when the bar is inactive. Eachstriker bar is provided at its lower end with a head 26,and pivoted to this'head is a lever 27, the number of leversQT correspondingto the number of lever keys 10. Each lever 27 is mounted upon a pivot pin 28, the latter being carried by a bracket 29, the several brackets being mounted upon a cross bar 30, as shown, a I 7 Supportingbrackets 33 sustain the weight of the magnet bar 49,: as hereinafter ex-, plained, andare connected to said magnet bar by bolts 31. Each supporting bracket 33 is mounted upon a supporting bar 32, the latter being provided withteeth 34, and, the supporting bracket 33] being similarly providedv withmating teeth, as will be. under A stop plate 19 is secured upona fastening 20and serves as a stop for the I stood from F ig. The supportingbracket' is v provided with a threaded stem 35,. and

fitting? upon thelatter isaniit :36, the stemi ilil '35 extending through a slot in the supporting bar 32. By loosening the nut 36 the bracket 33 may be adjusted up or down relatively to the supporting bar 32, and then clamped in position by rotation of the nut 36. The upper end of the supporting bar 32 is disposed adjacent to a bracket 32, and extending through this bracket is a threaded stem 32. The threaded stem is provided with revoluble nuts 32 disposed upon opposite sides of the bar 32. By turning the nuts 32 the position of the bar 32 relatively to the stem 32 may be shifted within reasonable limits, the general position of the bar 32 relatively to the board 9 being thus adjustable relatively to the levers 27. There are preferably two of the brackets 33, bars 32 and brackets 32, but the number may be increasedat'will. 7

Extending upwardly from the brackets 33 are arms 37 and journaled upon the latter is a power shaft 38. Located at one end of this power shaft is a pulley 38 (see Fig. 1)

by aid whereof the power shaft is turned.

The form of the actuating shoes may readily be understood from Fig; 7. Each actuating shoe is provided with a thick portion 39% and this portion carries a leaf spring 40. Connected with each leaf spring 40 is a tape 41 which extends through the slots 42, 43 in the leaf spring, as will be understood from Figs. 4 and 6. Each leaf spring 40 is held in position by aid of a fastening 44. In order to tighten the tapes 41 all that is necessary is to pull upon their lower ends or at the most to gently press the springs 40- downward'a little at their outer or free ends, and then adjust the tapes. The return of the leaf springs 40 to their normal position serves to secure the tapes. Each leaf spring 40 is provided with two ears 45 integral with it, and extending from its opposite edges, these ears serving to slidably engage the thick portion 39 of the actuating shoes and to prevent lateral movement of the springs 40 relatively to said shoes. Each actuating shoe 39 is provided with an arouate portion 46, the latter carrying a frictional contact surface 47. Each actuating shoe is provided with a hole 48 for receiving a pivot pin, as will be understood from Fig. 7

The magnet rail is shown at 49, and has generally the form of an elongated box which is made of magnetic material. Mounted upon the magnet rail is a bar 50 which is adjustable slightly in a direction crossing the length ofthe bar, and serves the purpose 7 'of a check, or limiting stop, for the actu ating shoes. Located within the magnet rail is a plate 52, and disposed between this plate and the oppositewall of the magnet bar are the magnets which are shown at 53. The'plate 52 is of insulating material, and is cutawayslightly, as indicated inFig. 3, a

conductor strip 54 being inserted into the plate 52 where thus cutaway. The plate 52 has a width a little less than the length of the magnets 53, and owing to this fact there is a little space at the lower edge of the plate 52. Disposed within this space is an electric cable 55, containing a number of separate wires 56 which are severally connected with the respective magnets 53. ires 57 also connected with these magnets lead therefrom to the contact strip 54.

screw bolt 67 the head 69 of which acts as a stop to prevent the armature contacting with the magnet core. Fastened on the un der side of th armature near its hinged end. 5 is a yoke 64 that extends beyond the free end of said armature and has two upwardly pro ecting arms 65 that support the actuat ing shoe 3O pivoted at 66 to said-arms. The

screw-bolt 67 projects through an opening in the yoke 64 and by. means of a nut 68 on said bolt, the yoke is raised and lowered and the position of the actuating shoe relatively to the shaft 38 adjusted. A screw 58 carried by the bracket 58 and adjustable therein is connected to one end of a spring 58*, the other end of which isattached to the yoke 64 or armature 63 to retract said parts when the magnet is deenergized;

second screw (50 adjustable in the bracket 58 has a head 62 that serves as a back stop for the armature and yoke. A pad 61 is secured on the yoke above the'head of screw 60 to muffle any sound when the yoke and screw come into contact. By this arrangement of parts, the bracket 58 maybe secured to the magnet rail 49. by a single fastening, a-sa screw (in practice two screws are employed) and carries the shoe, the armature, the hinge j construction and various ad usting devices 7 all in theform of a single composite unit. This feature is of great advantage in assembling the parts, in making repairs and in the manufacture ofinstruments.

In Fig. 5 is shown a slightly different form of armature mounting. A; bracket 75,

made of metal, is held upon the lower. portion of the magnet rail by a bolt '76, a leaf spring 77 being secured upon the bracket 75 and mounted upon this leaf s arin is the armature 78. Extending through this a'rma ture 1s. an ad ustlng screwFS).

yoke being provided with a hole through which the screw '7 9 extends. .The yoke carries the boss 82 'located upon its underside. The yoke 82 is provided'with arms 83 Revolubly fitted upon this ad ustlng screw is a nut81 whlch is adapted to e'ngagea yoke 82, tlllS' the latter is the actuating shoe 39. The adjusting screw '79 has-a head 85, which may be padded, and is adapted to engage the'adjacent portion of the magnet rail v Any convenient form'of back-stop, such as a screw botS'T, provided with a head 89 maybe provided to limit the retraction of the armature and the distance separating the actuating 'shoe- 39 from the shaft The screw bolts 87 are thus arranged in a row so that the severalheads 89' are in alinement with the several bosses 82 carried by the yokes 82. By adjusting the screw 79, by

aid of the nut 81, theplay of the armature 7S relatively to the magnet rail and the shoe relatively to the shaft .38 is controlled at will. A further adjustment'of the armature is attained by adjusting the screw bolt 87 relatively to the rail 86 and securing the screw bolt in position after such adjustment by any suitable means. The armature 7S is yieldingly attached to the bracket by the leaf spring 77. ported by any suitable means, such, as by two or more brackets similar in constri'lction to the brackets 58 that supportthe stop screws 60, as shown in the construction illustrated in FigsJS and 4. lVhenever the magnet 53 is energizedit actuates the armature 78, and as thisarmature carries the yoke 82, the yoke swings upward upon the leaf spring 77 as a center, so that the upper or arcuate surface of the actuating shoe is brought against the power shaft 38.

For the purposeof turning the power shaft 38 I provide a belt 89 (see Fig. 1) which engages the pulley 38" and is connected with a pulley carried by a motor 90. Connected with this motor is a cable 91 which leads to a primary battery 92.

The operation of my device is as, follows: The" parts being arranged as above described, and the circuit through the electromagnet being connected. up in the usual or any desired manner to-a contact device (not shown) for the purpose of enabling the magnets to be energizedand,deenergized by a music sheet and tracker board, or by any equivalent arrangement, and themotor being driven by aid ofthe battery. 92, the work of my improved mechanism will be understood. ergized it attracts its armature and causes the, yoke, carried by said armature, to swing upward and. force the adjacent actuating shoe into engagement with'the power shaft, this shaft having a rotary. motion (clockwise according to Figs. 3 andfi), and cansing the actuatingshoe to kick to the left, that is in a contra-clockwise direction so as to exert a sharp and sudden pull upon the )ceriesponding tape 41,. This tapethereupon pulls upon the corresponding lever'27, and

by tilting this lever forces the correspond. I

The rail'SG may be suptake place with precision.

Eachtime a magnet 53 is en ing'striker rod upward, thereby exerting a pushing force against a key lever 10, and actuatlng 1t and the hammer action associated with the key in question, and causing the proper string 13 to be struck. The damper action is operated directly. by the key lever. As the key lever is tilted the shoub der 21 engages the projection 17 and tilts the damper lever 15' which by pressing up-' ward against the damper rod 16 lifts the damper 14L fron'rthe string. \Vhen the circuit through the-magnet is broken theparts drop back to their respective normal positions; a

It will be noted that the levers -27 '(see Fig. 2.) are located'below theboard- 9 and consequently outside of the piano casing. They are thus situated in, a good position to facilitatethe fasteningfof the tapesv 41 upon power of the as dea" flexible connectionand exerts a suspensory action upon the actuating shoe 39, this shoe does not bear any weight of any of the parts, and consequently has great freedom and mobility ofaction so that its movements Except for the use of the flexible, connections consisting of the tapesl, tl'ieweight of the striker rods 22, rear ends of the key lever 10 and various other parts, would rest directly upon the actuating shoes and interfere to a greater or lesser extent with the action of the latter.

- are brought more readily and completely under control of the power shaft.

It will also be noted'that the supporting bar 32 is adjustablerelatively to the stem 32 so that the power shaft, magnet rail, and.

various parts grouped therewith, areas a unit adjustable toward or from the group i of levers 27, as will be understood from Fig. 2. This enables the flexible connectionsto be directed atdifferent angles relativelyto the levers 27 and constitutes in effect a form ofadjustment. Besides this the bracket 38,

I being adjustable relatively to the supporting bar 32,-en'ables the power shaft, magnet rail,

and various other parts to, be adjusted to different elevations relatively to the piano. The several flexible connections are indi vidu'ally adjustable as above described, as they can be drawn to any desired extent through their respective leaf springs 40 and secured by tension of the same.

Mounted below the board 9 1 s a rocking pivotally connected to a sliding bar 98; the

latter is pivotally connected to a short lever 99. This lever is mounted upon a pivot pin 100 and is adapted to be rocked upon its mounting by hand. The operator by swinging the short lever 99' moves the rod 98 lengthwise and rocks theshaft 93 so as to bring the leaf springs 96 severally into or 'outof engagement with the piano keys. The

piano may thus be shifted from a condition for automatic playing for one, for hand play mg.

upon the pianokeys cause the rear end of the keys tomaintain good contactwith the upper ends 24 0f the strlker bars 22, thus preventing lost motion. As a consequence the frequency with which the keys may he actuated without impairment to their functions is greatly increased. For instance, a particular key being pressed upon by its particular spring is held with a gentle pressure upon the corresponding striker bar. If now,

under control of the playing mechanism the striker bar moves upward say two or three strokes in rapid succession, upon each descent of the striker bar it is followed closely by the rear end of the key so, that there is no lost motion and no loss of time due to any lagging action by the key in following the striker bar. This is of very great importance where the music is to be played rapidly or where a particular note is. re peated in rapid succession. Except for the leaf springs taking care of this matter as above explained not only would the unclesirable lost motion be developed, but even false rattling sounds of a mechanical nature might be mtroduced.

Having thus described the invention what is clalmed as new 1s:

1. An electrically operated player for musical instruments comprising a plurality of levers, means for pivotally mounting the same upon the underside of a piano, striker rods connected with said levers and extending through the bottom of said piano into engagement with; the key levers thereof, mechanisms for actuating said levers, and a flexible connection between each lover of the plurality of levers and an actuating mechanism.

2. An electrically operated player for musical instruments comprising striker rods for engaging the actuating elements of the instruments, a plurality of levers connected with said striker rods. arail. support ng sald 7 levers, actuating shoes, flexible connections between said levers and the actuating shoes, a power shaft for swinging said actuating shoes, andelectrlcally operated means for The leaf springs by pressing gently forcing said actuating shoes into engagement with said power shaft.

The combination wlth a piano casing, a

netic devices each supporting one of said shoes and adapted to move the same 1nto engagement with said rotating shaft.

fic- The combmatron with a piano casing, a

hammer action mounted therein, and key levers for actuating said hammer. action, of

striker rods arranged to actuate said key" levers, levers without the casing connected to said "striker rods, actuating shoes, a flexible connection between each lever and an actuating shoe, a rotating shaft, electromagnetic devices including armatures upon which said shoes are pivotally mounted, and means for energizing said magnets to 'cause the en-' gagement of the actuating shoes with the rotating shaft. l r 5. The combination with a piano casing, a

hammer action mounted therein, and key levers for actuating said hammer action, of

striker rods arranged to actuate said key levers and having a limited downward movement, levers connected to sald striker rods,

actuating shoes, at flexible suspending member between each lever and an actuating shoe to relieve said shoes of. the weight of said key levers and associated parts, a rotating shaft, and electrically operated means for moving said actuating shoes into engagement with said shaft.

6. A grand piano having an electrically operated playing mechanism associated therewith, said mechanism being located be low the key bed of the piano and comprismg a plurality of vertically movable striker rods extending up through openings in the key bed, levers pivotally' supported below the key bed and to which said rods are re spectively pivoted, a power shaft, inverted actuating shoes arranged below said power shaft, a flexible connection between each shoe and its associated lever, andelectro-mechanical means for bringing said actuating shoesinto and-out of engagement with the power shaft.

7.'The"combmat1on of a muslcal instrument provided with keys and a casing, sup- 7 porting bars carried by said casing and adjustable thereon,- brackets Inounted' upon saidv su'pportingbars and independently adjustablebodily along the same, player mechanism mounted upon saidbrackets and ad justable therewith relatively to said supporting bars, and connections from said player mechanismto the keys of the musical instrument. 1 I

8. The combination with a piano casing and an action including keys, of striker rods for actuating said keys, levers located below said piano casing and connected tov said striker rods, actuating shoes, flexible connections therefrom to said levers,a magnet rail located below said levers and supported by the piano casing, said magnet rail having the form of a box and open at its bot-" tom, electro-inagnets mounted within said magnet rail and disposed vertically, armature sustained by said magnet rail below the electro-magnets andpivotally supporting said actuatingshoes, and a, rotatable shaft for actuating said shoes when brought into engagement therewith by said electro-' magnets.

9. The combination ofan actuating shoe, a power shaft for causing the same to swing, an armature provided with means for moving said actuating shoe into and out of en gagement with said power shaft, a spring clip mounted upon said actuating shoe, a flexible connection extending through said spring clip and held by pressure thereof against said actuating shoe, and mechanism controllable by said flexible connection for actuating a musical instrument;

'10. The combination of a power shaft, an actuating shoe movable'toward and from the, same, mechanism controllableby said actuating shoe for causing a musical instrument to sound, an armature provided with witnesses.

-against said pOWer shaft, a bracket for supporting said armature, saidbracket having a portion extending therefrom and bent substantially 1nto U-shape, a back stop carried bv said portion ofsaid bracket for stopping movements of said armature in one direction, a spring connected with said portion and with said armature for retracting said armature, a magnet rail for supporting said bracket, and an 'electromagnet carried by said magnet rail for attracting said armature. I

In testimony whereof I have hereunto 1 set my hand in presence of two subscribing CHARLES Vitnesses:

/JOHN L. CoRNoc, WV; C. RAIsNER.

W. DORRICOTT.

copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

7 Washington, I). G. 

